Online Packet Scheduling with Bounded Delay and Lookahead

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F16%3A10331740" target="_blank" >RIV/00216208:11320/16:10331740 - isvavai.cz</a>

Result on the web

<a href="http://drops.dagstuhl.de/opus/volltexte/2016/6790/" target="_blank" >http://drops.dagstuhl.de/opus/volltexte/2016/6790/</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.4230/LIPIcs.ISAAC.2016.21" target="_blank" >10.4230/LIPIcs.ISAAC.2016.21</a>

Result language

angličtina

Original language name

Online Packet Scheduling with Bounded Delay and Lookahead

Original language description

We study the online bounded-delay packet scheduling problem (PacketScheduling), where packets of unit size arrive at a router over time and need to be transmitted over a network link. Each packet has two attributes: a non-negative weight and a deadline for its transmission. The objective is to maximize the total weight of the transmitted packets. This problem has been well studied in the literature, yet its optimal competitive ratio remains unknown: the best upper bound is 1.828 [Englert and Westermann, SODA 2007], still quite far from the best lower bound of phi, approx. 1.618 [Hajek, CISS 2001; Andelman et al, SODA 2003; Chin and Fung, Algorithmica, 2003]. In the variant of PacketScheduling with s-bounded instances, each packet can be scheduled in at most s consecutive slots, starting at its release time. The lower bound of phi applies even to the special case of 2-bounded instances, and a phi-competitive algorithm for 3-bounded instances was given in [Chin et al, JDA, 2006]. Improving that result, and addressing a question posed by Goldwasser [SIGACT News, 2010], we present a phi-competitive algorithm for 4-bounded instances. We also study a variant of PacketScheduling where an online algorithm has the additional power of 1-lookahead, knowing at time t which packets will arrive at time t+1. For PacketScheduling with 1-lookahead restricted to 2-bounded instances, we present an online algorithm with competitive ratio (sqrt(13) - 1)/2 approx. 1.303 and we prove a nearly tight lower bound of (1 + sqrt(17))/4 approx. 1.281.

Czech name

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Czech description

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Type

D - Article in proceedings

CEP classification

IN - Informatics

OECD FORD branch

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Project

<a href="/en/project/GA14-10003S" target="_blank" >GA14-10003S: Restricted computations: Algorithms, models, complexity</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2016

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Article name in the collection

27th International Symposium on Algorithms and Computation (ISAAC 2016)

ISBN

978-3-95977-026-2

ISSN

1868-8969

e-ISSN

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Number of pages

13

Pages from-to

1-13

Publisher name

Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik

Place of publication

Dagstuhl, Německo

Event location

Sydney

Event date

Dec 12, 2016

Type of event by nationality

WRD - Celosvětová akce

UT code for WoS article

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